Automation has been used to simplify life in many areas. Examples include the use of robotic lawnmowers and vacuum cleaners that operate with limited human intervention.
These devices often use a form of perimeter marking, and use random paths to accomplish their tasks. The perimeter marking often involves the use of beacons, IR LEDs, electrified wires, metallic strips, GPS, radio frequency tags, radio transmitters or receivers, ultrasonic sensors, or other external markers.